Broaching machine



AZ- 19, 1941. F. J. LAPOINTE BROACHING MACHINE iFiled Jan. 1o, 19,58

4 snets-sheet 1 Inf/@12525211 JL llg- 19, 1941- F. J. LAPolNTE BROACHING MACHINE Fi1.ed.Jan. l0, 1938 4 SheebS-Sheec 2 AUS- 19, 1941- F. J. LAPolNTE 2,253,303

BROACHING MAGHINEy Filed Jan. 10, 1958 4 Sheets-Sheet 5 AJg- 19, 1941- F. J. LAPolNTE 2,253,303

BROAGHING MACHINE Filed Jan. l0, 1958 4 Sheets-Shea?I 4 Patented Aug. I9, 1941 BROACHING MACHINE Francis J. Lapointe, Ann Arbor, Mich., assigner, by mesnc assignments, to American Breach r Machine Co., Ann Arbor, Mich., a corporation of Michigan Application January 1o, 193s, serial No. 184,176

17 Claims.

The invention relates generally to breaching machines and more 'particularly to breaching machines employed for performing internal breaching operations.

A general object of the invention is to perfect a breaching machine and particularly an internal breaching machine of new and improved `construction with enhanced performance, output and ease of operation and control.

A more particular object of the vinvention is to provide a breaching machine having a new and improved automatic breach handling mechanism.

Another object is to provide an internal broachingmachine having a main slide or ram for imparting a breaching stroke to a-broach and a new and improved internal breach handling mechanism ceoperable with the ram to support both ends of the breach throughout the major portion of the breaching stroke. Y

Yet another object is te provide in a breaching machine, having a main slide er ram for imparting a breaching stroke to a breach, an automatic internal breach handling mechanism including an elevator for handling the breach before and after the breaching stroke, the elevator being slidably mounted directly en the main slide to have both movement therewith and a movementrelative thereto 'enabling the breach .to be accurately and rigidly supported at one end by the elevator during the major portion of the lbreaching stroke.

A further Objectis to provide a broaching machine having a fixed work support, a main slide for imparting a pull breaching stroke to an internal pull breach having means for engaging the breach disposed on one side of the work support, a new and improved breach handling mechanism including an elevator slidably mounted on said main slide on the side of the Werk support opposite the breach` engaging .means of the slide for movement both with and withdraw said fixture prior to such return stroke.

Yet a further object iste provide in a breaching machine having a Werk supporting fixture, means for imparting a breaching and a return stroke to a breach, automatic breach handling mechanism and control means for arresting said machine at the end of a breaching stroke and Iat the end of a return stroke, a, manually actuable means operable to initiate a breaching stroke and to lock said Work ilxture prior to such stroke and to initiate a return stroke and to Other objects and advantages will become apparent from the following detailed description` taken in connection with the accompanying dra-wings, in which:

Fig. 1 is a side elevational view partially in sectien of a preferred fom of breaching machine embodying the features of the invention.

- Fig. 2 is a front elevational view of the breaching machine shown in Fig. l.

Fig. 3 is a sectional view taken approximately along the line 3-3 of Fig. 2 looking in the direction of the arrows.

Fig. 4 is asectional view taken approximately along the line 4--4 of Fig. 1, looking in the direction of the arrows. y

v Fig. 5 is a diagrammatic view of the hydrauli circuit of the breaching machine shown in Fig. 1.

Fig. 6 is a diagrammatic view of the electrical control circuit of the machine shown in Fig. 1.

While the invention is susceptible of various. modifications and alternative constructions, it is shown in the drawings and will be described hereinafter in a preferred embodiment, but it is not intended that the invention is to be limited thereby to the specific construction disclosed, but it is intended to cover all modifications and alternative constructions falling within the spirit and scope of the'inventien as defined by the appendedv claims. p

Though the invention relates to breaching machinesbroadly, it is more particularly directed to breaching machines adapted for internal breaching operations. In such internal breachingV operations the handling of the breach, thatv is,` the loadinggof, the breach through the work and the Vpositioning of the breach so that the work' piece may *be/removed before a return pending upon thetime spent in such handling stroke vof thebroaeh takes place, and similar operations, presents a major problem for, de-

ef the breach, the machine and the attendant may be emcient and productive or ineilicient and v essential, particularly in internal pull broaching operations, that the broach be guided at bothends through its entire broaching stroke. It is to the provision of a broaching machine having a broach handling mechanism which not only operates efliciently, so as to cause the broaching machine to have a high production rate, but which also rigidly and accurately guides one end of the broach through the major portion of its broaching stroke, that the broaching machine described herein has been perfected. This broaching machine has, in addition, control means which automatically coordinates the operations of the broach handling mechanism with the other operations of the machine so that the desired eicient operation of the machine is obtained.

A vertical broaching machine of the internal pull broaching type has been chosen to illustrate the preferred embodiment of the invention, but it is to be understood, of course, that the invention is also applicable to other machines such as horizontal machines," machines in which the broaching stroke is up instead of down as here or return stroke, @the slide being of suiclent length at all times to extend to the opposite side or, in the present instance, above the work supporting table. Also located at the front of *the machine is the broach handling mechanism including an elevator disposed on the side of the table opposite the broach engaging means of the power slide, that is, above. This elevator is adapted to support the broach before a broaching stroke for loading the broach through the Work into engagement with the broach engaging means of the main slide and to support the broach after a return stroke for disengaging the broach from the main slide and elevating it above the table at the end of a return stroke to permit the loading of a new work piece. In the present instance, this broach handling mechanism is of unique construction in that the elevator is slidably mounted directly upon the broach actuating slide so as to be both movable therewith and movable relative thereto. This unique mounting enables the elevator to guide one end of the broach rigidly and accurately through the major portion of the broaching operation. The main slide and the broach handling mechanism herein are hydraulically actuated under a semiautomatic electrical control system.

In a position at rest, the broach actuating slidey is retracted to an uppermost initial or starting position, such as that shown in Fig. 1, `and the elevator of the broach handling mechanism also is retracted to an uppermost initial or starting position, in which position the broach or breaches carried by the elevator are disengaged from' the broach actuating slide and are elevated above the work supporting table a distance such that a work piece may be loaded on the table. After a work niece has been loaded on the work supporting table. a cycle of operation is initiated manually by actuation of a suitable part of the electrical control system and, as an incident to such actuation, the elevator first moves relative to the main broach actuating slide toward the work supporting table -to load the broach through the Work and the table into the broach engaging means of the broach actuating slide. Approximately simultaneously with the engagement of the broach with the broach engaging means of the main slide or preferably just slightly subsequent lthereto, so as to insure engagement of the broach, the elevator trips a switch of the electrical control system to initiate movement of the broach actuating slide von a broaching stroke. During such broaching stroke, the elevator moves with the broach actuating' slide, thus accurately and rigidly guiding the upper end of the broach through the major portion of its broaching stroke. Near the end of the broaching stroke, the elevator is arrested by engagement with a iixed abutment while the slide continues, thereby di'sengaging the broach from the elevator, to complete the broaching stroke and to draw the broach through the work to an extent such that the work is free to be removed. 'I'he broaching stroke o f the slide is arrested by the tripping of a suitable-switch of the control system by the slide as it reaches the end of the broaching stroke.

The elements are now all at rest and to complete the cycle the attendant rst removes the work piece and then again actuates manually a switch of the control system, initiating the second or return half of the cycle. In this half of the cycle the movements of the main slide and the elevator are reversed as to sequence with the main slide having an initial return or upward movement. In such upward movement the broach is passed through the Work support and into engagement with the elevator after which the elevator and the slide are returned simultaneously until the slide reaches its initial position. As an incident'. to reaching that position it actuates a switch of the control system which in tum causes the elevator to be moved Ithrough the remaining distance relative to the main slide to its initial position in which the broach has been entirely withdrawn through the work supporting table to a position well above the table enabling a new work piece to be loaded.

Referring now more particularly to the drawings, I0 represents the base of the broaching machine upon which is mounted a vertically disposed frame I I. Fixed on the front of the frame II is a work supporting table I2 disposed intermediate the bottom and top of the frame, in the present instance approximately at a height providing for the convenient loading or unloading .of work pieces onto the table by an attendant of the machine. The table I2 carries a work supporting fixture generally designated I3, which may be actuated to lock the work piece in broaching position or may be actuated to an unlocked and withdrawn position permitting the work piece to be removed. Disposed below the work supporting table I2 is a conventional chip pan I6 which may be considered as forming a part of the frame I I.

The frame I I is in large part hollow to accommodate the elements of the hydraulic power system and the elements of the electrical control svstem, and has formed in its front face (see Figs. 2 and 4) vertical Ways I5 which Vextend from the base substantially to the top of the frame. Reciprocable vertically of the frame past the table I2 is the broach actuating slide, here designated IS, which is formed with oppositely disposed flanges I7 slidable in the ways I5 and retained and guided therein by means of vertical plates I9 removably secured to the frame II by means of bolts I9. At its lower end, the slide has a lateral extension' 22 projecting forwardly beneath the table I2. In the present instance, thisextension c'arrles a pair of broach engaging means 23 of some conventional construction enabling the same to receive and secure the end of a broach forced into the end thereof and releasing the broach when the engaging means 23 strike a suitable part of thetable I2, as an inci'- dent to the return of the slide to its uppermost or initial position. While two such broach engaging means are disclosed herein, it is to be understood that any number may be provided, depending upon the number of broaches to be employed. p

lIn the present instance, the slide I9 is of unusual length to provide aunique mounting for the elevator or carrier of the broach handling mechanism. Accordingly the slide I9 is formed at its upper end with an extension 25 (Fig. 3)

lyieldably to retain broaches 29 forced thereinto.

As can be seen in Fig. 2, the sockets comprise simply a spring pressed plunger 30 which .is yieldably urged into engaging relation with an annular groove 3| formed in the upper end of the broach 29 and thus permitthe insertion or withdrawal of 4a broach by the application of force to the broach.

The elevator 21, of course, as previously stated generally, has a predetermined movement both relative to and jointly with the slide I6 such that it rst moves relative to the slide to load of the broaching stroke is arrested, while the slide I6 continues on its breaching stroke and in such movement withdraws the broaches 29 from the sockets 28 to complete the broaching stroke and to draw the broaches through the work pieces so as to permit removal thereof. Conversely, upon the return half of the cycle of the machine, the slideA I6 has an initial movement relative to the elevator 21 inwhich the broaches 29 are passed upwardly through the tablel I2 and are forced into sockets 28 after which the elevator and the slide move jointly until the slide reaches its initial position, after which the elevator has a movementl relative to the slide in which the lbroaches 29 being released from the engaging means 2,3 are drawn upwardly by the elevator to a suilicient height above the table to permit the loading of new nated movement` of the elevator andthe slide, nor the exercise of extreme care and of compensatlon for wear to assure proper alinement of the elevator and particularly of the broaches when supported and guided by the elevator.

The slide I9 and the elevator'21 each has a power means for actuating the same and,while the power means may take a variety of forms, a preferred form is a hydraulic motor as disclosed herein. In the case of the main slide I9, the hydraulic motor is composed of a piston 35 and a cylinder. which -hereinconstitutes the movable element of the motor and, for the sake of strength and rigidity, is formed as an Integral part of the slide I9. The piston 35 being the stationary element has a piston rod 31 which extends through the upper end of the cylinder 39 and is anchored in a block 38 at the top of the frame II. To supply fluid to the head end of the cylinder, the piston rod 31 in conventional manner is made hollow and has extending therethrough a duct or tube 49 which projects downwardly through the piston to communicate with the head end of the cylinder 39. The annular space between the rod 31and the duct 40 constitutes a passage 4I for the supply and return ',of fluid to and from the rod 'end of the cylinder and, accordingly, the piston rod 31 adjacent the piston 35 is formed with aper-- tures 42 (see Fig. 5) providing communication between the annular passage 4I and the of the cylinder.

In the case of the elevator 21, the hydraulic l motor also comprises a vertically disposed cylinder 45 and a piston 46 reciprocable in the cylinder and havinga rod 41 projecting through the upper end of the cylinder 45 and into engagement with the elevator 21. The cylinder 45 is disposed in the chip pan I4 in front of the guideways I5 and extending upwardly through they table' I2 and to accommodate the cylinder ythe extension 22 is provided with an aperture 48.

For driving the motors of the slide I6 and of the broach handling mechanism, the invention contemplates provision of a hydraulic power system. For a more ready understanding, this system is disclosed diagrammatically in Fig. 5, and it will be seen from a reference to Fig. 5 that the system is composed of a high pressure circuit for actuating the broaching slide or ram I6 and of a comparatively low pressure circuit for actuating the broach handling mechanism.. Referring more particularly to Fig. 5, hydraulic iluid under pressure is supplied to the high pressure circuit by means of a large output, high pressure ram pump RP whose inlet is connected by means of a conduit 55 to a tank or reservoir 56 for storing suitable hydraulic fluid, preferably oil. The ram pump RP is driven by suitable means, such as an electric motor 51 (see Fig. l), and discharges fluid under pressure to a supply line 59 which discharges to a four-way valve 6I).

work pieces on the table. It is believed apparent y The valve 69 is connected by a conduit 6I to the conduit 40 opening through the piston 35 so as to communicate with the head end of the cylinder 39. The rod end of the cylinder 39 is connected with the valv'e 60 through the medium of the annular passage 4I, previously described, and a conduit 62 which communicates at one end with the passage 4I and at the other end with the'valve 6I). A return conduit B3 leads 'from the valve 60 to the reservoir 56.

To limit' the pressure thus built up in the cirlcuit, particularly the supply side thereof, there is connected to the supply line 59 a relief valve rod end conduit 64 which is adjustable to maintain a predetermined maximum pressure limit in the supply line 59 which, if exceeded, will cause the valve 64 to open and discharge to the tank 55 .through a 65. 'I'his valve, moreover, is adapted to be controlled by safety valves 66 and 61 connected thereto by means of a common conduit 68. The valves 66 and 61 are not new per se, but are of the type which function upon being actuated to vent the valve 64 and thus cause the same to permit discharge of fluid from the supply line 59 at no pressure. Interposed in the conduit 68 is a valve 69 whichmay be manually actuated to close or open the conduit 68 and thus remove or place the valve 64 from or under the control of the valves 66 and 61. To control the rate of movement of the slide orA ram. I6 during the broaching stroke, there is connected to the conduit 6| a feed control device 15 which is adjustable to by-pass varying quantities. of fluid and thus vary the rate at which the ram I6 is driven by the pump RP. Interposed in the conduit 62 is a by-pass and check'valve 'I6 which permits free iiow of uid from the valve 68 to the rod end vof the cylinder to effect a return stroke of the ram, but restricts the ow of fluid from the rod end of the cylinder to the valve 60 during the broaching stroke of the ram so as to prevent overrunning of the ram.

Valve 60 has three positions, namely, a neutral or normal position, which is that in which it is shown in Fig. 5, and a position on either side of neutral in which fluid is supplied respectively to the conduits 6I and 62. In the neutral position of the valve 60 no uid is supplied to or discharged from either of the conduits 6| and 62, but is by-passed directly to the return conduit 63. The control of the broaching machine being electrical, the valve 60 is actuated by the energization of solenoids A and B. Energization of solenoid A shifts the valve 60 to a position causing pressure fluid to be supplied through the conduit 6| to the head end of the cylinder 36 to eiect a broaching stroke, and energization of the solenoid B shifts.the valve 60 to a position causing pressure fluid to be supplied through the conduit 62 to the rod end of the cylinder effecting a return stroke of the ram. Conduits 6| and 62, of course, also function in well known manner to conduct exhaust fluid from the cylinder 26 to valve 60 from which it is returned to the reservoir 56 through conduit 63. The valve with its solenoids A and B is biased to return to neutral position when both' solenoids 'A and B are deenergized.

Pressure fluid for the low pressure circuit of the broach handling mechanism is supplied by a-small output, low pressure pump LP supported from the casing of the pump RP and driven from a common shaft bythe electric motor 51. This pump draws fluid from the reservoir 56 through a conduit 8U and discharges to a fluid supply line 8| which leads to a four-way valve 82. The four-way valve 82 in turn is connected by a conduit 83 to the rod end of the cylinder 45 and is connected by a conduit 84 to the head end of the cylinder 45, while a return conduit 85 leads to the reservoir 56. Connected in the supply line 8| is a relief valve 81 operable to discharge iiuid to the reservoir 56 through a conduit 88 should the pressure in the supply line 8| exceed the limit for which the relief valve 81 is set. Interposed in the conduit 8,4 is a by-pass and check valve the valve 82 to the cylinder 45 for raising the elevator 2l but which restricts and retards the flow in the opposite direction through the conduit 84 so as to prevent the elevator from overrunning the pump LP.

Like the valve 60, valve 82 has three positions, namely, a neutral or normal position which is that in which it is shown in Fig. 5, and a position on either side of neutral in which fluid is supplied respectively to the conduits 83 and 84. In the neutral position of the valve 82, the supply line 8| as well as the conduits 83 and 84 are connected to the reservoir through the return' conduit permitting a free interchange of iiuid between the head and rod end of the cylinder 45 at no pressure. The control of the breaching machine being electrical, the valve 82 is shifted from its neutral position by the energization of solenoids M and N provided for that purpose. Energization of solenoid M shifts the valve 82 to a position causing pressure fluid to be supplied through the conduit 83 to the rod end of the cylinder 45 to effect a movement of the elevator 21 loading the broach through the work. Energization of the solenoid N shifts the valve 82 in the opposite direction causing the pressure fluid to be supplied through the conduit 84 to the head end of the cylinder 45 and raising the elevator 21. Conduits 83 and 84, of course, also function in well known manner as return conduits permitting exhaust fluid from the cylinder 45 to be returned to the valve 82 and hence through conduit 85 to the reservoir 56.

It is essential for the proper operation of the broaching machine here disclosed that the movements of the main slide or ram and of the broach handling mechanism be precisely, coordinated and timed. Accordingly a, semiautomatic control system is provided herein which, as previously stated, is electrical in character. Like the hydraulic system, the electrical control system is composed of a high voltage circuit for controlling the solenoids A and B of the high pressure ram circuit and a circuit of low voltage for controlling the solenoids M and N of the low pressure broach handling mechanism circuit. The electrical control system is disclosed diagrammatically in Fig. 6, to which in particular reference will now be made.

In addition to the solenoids mentioned, the circuits comprising the electrical control system include a plurality of relays RA, RB, RM, RN and RS, a plurality of switches actuated by the ram or the elevator, and a plurality of manual push button switches. Of the relays, RA and RB -control respectively switches C--A' and C-A2, and C-B and C-B2, which are open when the relays are deenergized and closed upon energization of the relays. As their designation suggests, these switches and relays are associated with the solenoids A and B. In addition the relay RA controls a third switch C--A3 which also is open when the relay is deenergized and, as will shortly become apparent, is connected in the low voltage circuit. The relay RM controls a plurality of switches C-M and C--M2 both of which are open when the relay RM is deenergized and are closed upon energization of the relay RM. Similarly, the relay RN controls, switches C-N' and C--N2 both of which are open when the relay is deenergized and closed upon energization of the relay. The relays RM and RN and the switches controlled thereby are, as their designation indicates, associated respectively with the solenoids M and N. The relay vice and in the presentinstance has a single switch ES2 which remains in either an open or a closed position depending upon to which position it has last been actuated. In the present instance the switch is actuated `toa closed position in the upward orreturn movement of the elevator 21 and isactuated to an open position as an incident to a downward or loading by the elevator 21 of the broach handling`mech` anism. 'I'he switch devices may be'simple devices, that is, composed of but a single switch,

or compound devices, that is, composed 'of aplu- Preferably the switchespf A the switch devices are'suitably enclosed to prorality of switches.

tect the same. The switch device ES2 is a maintained contact switch device, that is, the device .remains in the position to which it has been actuated. Switch devices RSI, RSZ and ESI and ES3 on fthe other hand are not maintained switch devices, but have a normal position which is the free position and an actuated position which is that assumed when the switch device is engaged by suitable means such as cams or dogs on the ram or the elevator.

As best seen in Fig. 6, the switch device RSI is la compound device having switches RSI', RSI. The switch device RSI, as seen in Fig. 2, is mounted on the frame I I near the top thereof to be actuated by a cam dog DI carried by the ram I6 when the latter is in its initial or withmovement of the elevator 21.

In addition to the automatically actuated switches described, the electrical control system includes five manually "actuated switches MSI,

drawn position. In this actuated position of the switch device asl, the switches Rsl' and Rs|2 are 4respectively open and closed. When the ram moves downwardly on the broaching stroke and the switch device RSI is released to assume its normal position, the switches RSI' and RSI2- will assume their normal position which is respectively closed and open. The switch device RSZ is a simple device having but a single switch RSZ which is closed in the normal position ofthe switch device and which is openA when the switch device is actuated. Theswitch device RSZ (see Fig. 2) is mounted on the frame II MsalMsa, Msi and Mss. of these, switch MSI is a starting switch which is biased to open position and 'is momentarily closed to condition the low voltage circuit. The switch MS2 is a normally closed switch and serves as an emergency stopA switch for arresting the machine,v

while switch MS3 is a special startingswitch normally biased to open position and intended to be closed for starting the ram on its broaching stroke after the ram has been stopped as an incident to an opening of the emergency stop switch MS2. These three switches just described are all mounted at the left front of the machine, as viewed in Fig. 2, where they are readily accessible to an operator standing before the machine., The switches MSII and MS5 are primary switches for initiating the broaching haii and the return half, respectively, of the cycle of operation of the broaching '.niachine. *These switches are associated with a lever 95 (see Figs. 2 and 5) which lever actuates the work supporting fixture I3. When swung to the position shown in Fig. 5, the lever 95 first locks the work supporting fixture vI3 and then actuates the switch MS4 to close the same for initiating the breaching half of the cycle by initiating downlever 95 is swung to the opposite position from 'that shown in Fig. 5, it first withdraws the work supporting fixture and unlocks the same so that the work may be removed and then actuates the switch MSS to close the same for initiating the devices having but a single switch ESI and ES3',

respectively. The switch ESI is normally closed and thus is open when actuated, while the switch l yES3 is normally open and thus is closed when the switch device ES3 is actuated. The switch devices ESI and ES3 are mounted on the frame il of the machine near the top thereof and opposite the switch RSI, as best seen in Fig. 2, in a position to be actuated respectively by a dog D4 and a dog D5 carried by the elevator 21. The dog D4 actuates the switch ESI when the elevator is in its uppermost or initial position, while the dog D5 actuates the switch device ES3 at the time the elevator 21 has moved downwardly sufliciently to load the broach through the work and engage the same in the means 23 of the ram I6. 'I'he switch device ES2 is mounted on the frame I I intermediate the switch devices ESI and ES3, but closer to the switch device ES3,

` and is adapted to be actuated by a dog DB (see return half of the cycle of the broaching ma- ,chine by initiating return movement of the ram Having described the relays, the switch devices and the switches actuated thereby, the connection thereof in the electrical control` system will now be described. As previously stated, the system comprises a high voltage circuit which includes the solenoids A and B for shifting the four-Way valve 60 in the high pressure ram circuit. Herein the solenoids A and B are connected in parallel between the main line wiresV Ll and L2 and connected in series respectively with the solenoids A and B are the relay control switches C-A and C--A2 and C--B and C-B2. The switches are connected on opposite sides of the solenoids A and B respectively, in order that the solenoids may be completely disconnected when the relays RA 'and RB are dee'nergized so as to avoid any possible energization of the solenoids by a short circuit.- Also connected between the line wires LI and L2 in parallel with the solenoids A and B is a primary winding P of a transformer T. Connected in the line wire L2 ahead 'of the solenoids and the winding P is a manually actuated switch 96 serving as a master switch controlling the entire electrical system.

The low voltage circuit which includes the solenoids for the valve 82, as well as all of the relays and the manually and automatically actuated switches, Iderives its energy from the high voltage circuit and to that end a secondary winding S of the transformer T is connected at its ends to wires L3 and L4. Connected across the wires L3 and L4 is the starting relay RS and connected in series therewith is the normally open starting switch MSI and the normally closed emergency stop switch MS2. It will thus be seen that energization or deenergization of the relay RS is controlled by the switches MSI andMSZ. As previously stated, the relay RS controls the switches C-S and C-S2. The former of these switches, namely C-S is connected around the normally open starting switch MSI so as to form a holding circuit for the relay RS once the switch MSI has been momentarily closed. The switch C--S'is disposed in the wire L3 to control the i'low of current to all of the remaining switches, solenoids and relays in the remainder of the low voltage circuit.

The solenoid M is connected between the wires L3 and L4 and has in series therewith on opposite sides the switches C-M and C-M2. These switches, as previously stated, are controlled by the relay RM which is connected between the wires L3 and L4 and has connected in series therewith the manual switch MS4 and also the maintained contact switch ESZ' which is controlled by the elevator 21. Connected in parallel with the relay RM is the relay RA having the manual switch MS4 common to the two relays. To that end the relay RA is connected at one end to the wire L4 and at the other end is connected by a lead to the circuit of the relay RM intermediate the switches MS4 and ES2. Interposed in the lead |00 is the switch RSZ and also interposed in the lead I00 in series with the switch RSZ is a parallel circuit IOI having the switch ES3 in one branch and the switch C--A3 in the other branch. In order that the relay RA may be energized independently of the switch MS4 and of the switches in the parallel circuit IOI a lead I 02 is connected at one end to the wire L3 and to the lead I00 intermediate the parallel circuit IOI and the switch RSZ. In the lead |02 is the switch MSS which it will be remembered is in the nature of an emergency switch or'continuing the downward or broaching stroke of the ram after it has been interrupted by an opening of the emergency stop switch MS2.

Like the solenoid M, the solenoid N is connected across the wires L3 and L4 and connected in series therewith on opposite sides thereof are the switches C-N and C-N2. The switches C--N and C-N2. it will be remembered are controlled by the relay RN. This relay is connected across the wires L3 and L4 and has in series therewith the manual switch MS5 and the automatic switches RSI2 and ESI. Connected in parallel with the relay RN is the relay RB. This relay has in series therewith the switch RSI' and the relay is connected at one end to the wire L4, while one terminal of the switch RSI' is connected to the circuit of the relay RN intermediate the switch MS5 and the switch RSI2, in order that the switch MSS may be common to the relays RB and RN.

'I'he operation and the function of the various switches, relays and solenoids as well as the valves controlled by the solenoids is most readily and best understood from the operation of the breaching machine. The operation of the machine will therefore be described briefly in order better to correlate the functional relationship of the various elements of the power and the con-- trol systems. For that purpose, let it be assumed that the ram or slide IB and the elevator 21 are intheir initial or withdrawn position as indicated in the drawings and that the switches and switch devices are in the positions indicated in the drawings. which positions correspond to the positions of the ram and the elevator, and to the dotted line position of the lever in Fig. 5.

Under such conditions, to start a cycle of operation the attendant of the machine would first start the electric motor 51 with the result that fluid under pressure would be supplied by the pump RP to the supply pipe 59 of the high pressure or ram circuit and fluid under pressure would be supplied by the pump LP to the supply.

line 8I of the low pressure or broach handling mechanism circuit. No movement of either the ram I6 or the elevator 21 would take place, however, because the valves 60 and 82 are in neutral position causing the fluid to be by-passed and returned directly to the reservoir 56 through the return conduits 63 and 85, respectively. Next the operator would close the switch 96 and would momentarily depress the manual switch MSI. Such closure of the manual switch MSI would energize the relay RS with resultant closure of the switch C-S' which would then complete a holding circuit for the starting relay RS permitting the' manual switch MSI to be released. 'Ihe switch C-S2 also would be closed thereby conditioning a circuit for the remaining relays and the solenoids M and N.

The machine is now conditioned for production and the attendant would next place a work piece to be broached in the work supporting fixture I3 and would then swing the lever 95 clockwise from the broken to the solid line position shown in Fig. 5. Such movement of the lever 95 would rst lock the work and the fixture in breaching position and in the final movement would close the switch MS4. Closure of MS4 would energize i the relay RM since, as can be seen in Fig. 6,

the maintained contact switch ES2 is now closed. As a result of the energization of the 'relay RM, the switches C-M and C-M2 controlled thereby would be closed, completing the circuit for the solenoid M and thereby causing the same to shift the core of the valve 82.

With the core of the valve 82 shifted, as an incident to the energization of the solenoid M, pressure iluid is now supplied through the conduit 8I, the valve 82 and conduit 83 to the rod end of the cylinder 45 to initiate downward movement of the elevator 21. During this initial downward movement, the ram I6 remains stationary and thus the movement of the elevator is relative to the ram and consequently the broaches 29 are loaded through the work piece and the work supporting table into the broach engaging means 23 carried by the ram I6. Substantially simultaneously with the reception of the ends of the broaches 29 in the engaging means 23, dogs D5 and D6 engage and actuate respectively the switch device ES3 and the switch device ES2, with the result that the corresponding switches ES3' and ESZ are reversed from the position shown in Fig. 6, namely, the switch ESZ is opened while the switch ES3 is closed. As a result the relay RM is deenergized causing the switches C-M and C--M2 controlled thereby to be opened and the solenoid M deenergized. Closure of the switch ES3', however, completes the circuit to the relay RA with the result that the switches C A and C-A2 are closed and the solenoid A energized. The core of the valve 60 is shifted by such energization of the 6I to the head end of the ram cylinder 36. Downward movement of the ram in a broaching stroke results and the broach is drawn through the work piece.

During the major portionof such breaching stroke of the ram I6, the elevator 21 moves with the ram and thus through the major portion of the stroke continues to guide and support the solenoid A so that pressure iiuid from the supply line 59 is nowv discharged through the conduit upper ends of the broaches 29 to assume proper g alinement of the broaches and thus a proper breaching operation. It is to be remembered that with the solenoid M deenergized thevalve 62 is returned to neutral position. thus permitting a free interchange ofv fluid between the ends of the cylinder 45 during the movement of the elevator 21 with the ram I6. Toward the end'of the broaching stroke, the elevator strikes an abutment B fixed on the frame and is thus restrained against further movement with the ram I6. The ram, however. continues its broaching or downward stroke and, as a result, the broaches are Withdrawn from the sockets 29 inwhich they are yieldably retained and are'also drawnvcompletely through the work piece. After the broaches are drawn completely through the work piece the dog D2 carried by the ram actuates the switch device RS2 and accordingly opens the switch RS2'. It will be apparent from a reference to Fig. 6 that such opening of the switch RS2 deenergizes the relay RA and, as an incident thereto, deenergizes the solenoid A, permittingl the core of the valve 69 to return to its neutral position. Thus at this point the ram and the elevator are at rest with no fluid under pressure being supplied to either the cylinder 36 or the cylinder 45.

To initiate the second or return half of the cycle of operation of the breaching *machina the attendant swings` the lever 95 from its engagement with the switch MS4 counterclockwise as viewed in Fig. 5 toward engagement with the switch MS5. The initial portion of suchswinging movement of the lever 95 withdraws the Work supporting fixture I3 and releases the work so that the same may be unloaded from the table and in the iinal movement closes the switch MS5 which was opened as an incident to the swinging of the lever 95 to initiate the breaching half of the cycle. Since the switch RSI' was closed as an incident to disengagement of the dog DI with the switch device RSI, closure of the manual switch MSS now completes a circuit for the relay RB which is energized and closes the switches C--B and C--B2 to energize the solenoid B. Energization of the solenoid B shifts the core of 'the `valve 69 to a position in which fluid under 'pressure from the supply line 59 is discharged through the conduit 26 to the rod end of the cylinder 36 to initiate a return stroke of the ram I6. During this initial return movement of the I ram I6, the elevator 21 remains stationary relative to the frame, the friction of the ways 26 not being suilicient to overcome gravity and other forces opposing movement, and thus the movement of the ram is relative to the elevator, with the result that the broaches 29 vare passed upwardlyV through the work supporting table and are forced into the sockets 29 of the elevator. From that point in the return movement of the through the dog DI actuates the switch device RSI again to open the switch RSI' and thereby deenergize the relay RB with the result that the solenoid B is deenergized permitting the core of the valve 60 to return to neutral position in which the supply of iluid to the rod end of the cylinder 36 is terminated. 'I'he switch ESI having been closed as an incident to the initial downward movement of the elevator 21, closureof the switch RSI2 as an incident to the actuation of the switch device RSI upon return of the ram to initial position completes the circuit for the relay RN, which thus closes switches C-N' and C--N2 to energize the solenoid N. With the energization of the solenoid N, the core of the valve 82 is shifted so that iiuid under pressure is supplied through the conduit 94 to the head end of the y cylinder 45. The elevator 21 thus is raised relaram I6 until it reaches its initial or fully retracted position, the elevator and the ram move tive to theram I6 and carries the broaches 29 with it since the devices 23 released the broaches as an incident to the return of the ram to initial position. The elevator 21 continues to rise until the dog D4 carried thereby strikes the switch device ESI, thereby opening thevswitch ESI' and breaking the circuit to the relay RN. With the relay RN deenergized the solenoid N is deenergized and the valve 82 returned to neutral position so that no fluid under pressure is supplied to the cylinder 45 and the entire machine is now again at rest. In this position of the elevator 21, the broaches are raised a suiiicient distance above the work supporting table so that new work pieces may be loaded thereon. In the initial movement of the elevator relative to the ram, the dog D6 again actuates the switch device ES2 to return the switchESZ to its initial or closed position to condition the circuit for the relay RM for the next breaching cycle; This does not energiz relay RM because switch MS4 is open.

Should it become necessary during the course of the operation, particularly during the broaching portion of the cycle to arrest the operation of the machine, this is readily done by depressing the emergency stop switch MS2 which would cause all the relays to be deenergized and thus cause all of the solenoids to be denergized, permitting the valves to return to neutral position. The machine may be again placed in operation to continue the breaching stroke by momentarily depressing the start switch MSI and the emer- Y gency start switch MS3.

Should the ram I6 for any reason travel beyond the normal limits, that is, those determined by the actuation of the switch devices RSI and RSLTie safety valves 66 and'61 would be actuated and would thus cause the relief valve 64 to discharge at no pressure to the reservoir 56, thus taking strain off of the packing of the ram. To restore the circuit and the ram to operation, the hand valve 69 is momentarily closed so as to withdraw the valve 64 from the control of the valves 66 or 61. the valve 69 to be opened again immediately after the ram has been returned within'its normal limits of movement.

-' I claim as myinvention:

1. In an internal pull broaching machine, a frame, a work supporting fixture mounted on said frame, a main powerdriven slide mounted on said frame for reciprocation relative to said work supporting xture, said slide having breach engaging means'near one end for one end of the broach and near the other end having a reduced portion providing longitudinally extending ways, Yand mechanism for handling the breach by its other end including an elevator slidably mounted in the ways of the reduced portion of the main slide.

2. In a broaching machine, a main broach actuating slide having at one end a lateral extension carrying broach engaging means and at the other end carrying parallelways extending longitudinally of the slide, and an elevator slidably mounted in the ways of said slide, power means for actuating said elevator, and control means for said power means causing said elevator to move with said slide and also relative thereto.

3. In a broaching machine, a broach actuating slide, broach engaging means at one end of said slide operable automatically to receive and engage a broach pressed thereinto and actuable to release the broach, an elevator slidable directly on said slide at the end opposite said broach engaging means in a direction parallel with the direction of movement of the slide, and means carried by the elevator for yieldably retaining a broach.

4. An internal pull broaching machine comprising, in combination, an upstanding frame, a work supporting fixture mounted on the front of said frame intermediate the ends thereof, vertical guideways formed in the front of said frame, a slide mounted in said guideways on the frame for vertical reciprocatory movement relative to said work supporting fixture, a lateral projection carried by the slide at its lower end, means carried by said projection for chucking one end of a broach, the upper end of said slide being formed with guideways extending longitudinally thereof, and mechanism for chucking the broach by its other end comprising an elevator slidably mounted in the guideways on said slide,

5. A broaching machine comprising, in combination, a Work supporting iixture, a power driven main slide for actuating a broach through a broaching and a return stroke, automatic broa-ch handling mechanism including an elevator for supporting a broach prior to a broaching stroke and subsequent to a return stroke imparted to the broach by said main slide, power means for -actuating said main slide and said elevator, and control means for said power means including manually actuable means for initiating the broaching half and the return half of the cycle of operation of the broaching machine, -and automatically actuated means for coordinating 'the movements of the main slide and the elevator and for bringing the same to rest at the end of the broaching half and the end of the return half of the cycle of operation of the machine.

6. An internal broaching machine having, in combination, a frame, a work supportingiixture mounted thereon, a main slide for carrying and actuating a broach reciprocably mounted on said frame, means secured to said slide and disposed on one side of the work supporting fixture for chucking one end of a broach, power means for reciprocating said main slide, automatic broach handling mechanism including a carrier slidably mounted on said main slide, means on said carrier for supporting a broach from its other end and power means for reciprocating .said carrier, and control means for said power means including a manually controlled member actuable in one direction to lock a work piece and the work supporting xture in broaching position and for initiating movement of said carrier in a direction to insert a broach carried thereby through the work piece and into the broach receiving and retaining means of said main slide and actuable in the opposite direction to unlock said work supporting iixture and initiate a return stroke of said main slide.

'7. A broach machine having, in combination, a work supporting fixture, a main slide for actuating a broach through a 'broachingv and a return stroke, means mounted on said slide near one end thereof for chucking one end 0f a broach, power means for reciprocating said slide, automatic broach handling mechanism including a carrier for supporting the broach from its other end, said carrier being slidably mounted directly on said main slide, and power means for reciprocating said carrier, and control means for said power means including manually actuable means for initiating the cycle of operation of the broaching machine and automatically actuated means for coordinating the movements of said main slide and said carrier to obtain a cycle of operation in which the carrier inserts a broach carried thereby through the work and into engagement with the broach chucking means on the main slide, guides the trailing end of the broach throughout the major portion of the broaching operation and at the end of the cycle withdraws the broach to a position spaced from the, work supporting fixture to enable the loading of a new work piece.

8. An internal pull broaching machine having, in combination, a work supporting fixture, a main slide for actuating the broach mounted for reciprocation relative to said work supporting fixture, means mounted on said slide near one end thereof for chucking one end of a broach, power means for reciprocating said main slide, automatic broach handling mechanism for the other end of the broach including a carrier mounted directly on said slide for movement both relatively to and jointly with said slide and power means for reciprocating said carrier on said slide, and control means for said power means including a first manually actuable device for initiating movement of said carrier relative to said main slide for inserting a broach carried by the carrier through a work piece and into engagement with the broach chucking .means on the main slide, a rst carrier actuated control device operable upon actuation to initiate a broaching stroke of said main slide and a second carrier actuated control device operable to arrest return movement of the carrier.

9. An internal broaching machine having, in

combination, a work supporting xture, a ram for actuating a broach through a broaching and a return stroke, means carried on said ram for chucking one end of a broach, an hydraulic motor for reciprocating said ram, automatic broach handling mechanism including a carrier slidably mounted directly on said ram for movement both with and relative to said ram, means on said carrier for releasably chucking the broach by its other end and an hydraulic motor for reciprocating said carrier on said ram, an hydraulic circuit including a source of uid under pressure and a plurality of control valves supplying operating fluid to said hydraulic motors to impart movements to said carrier and ram in a predetermined sequence and an electrical control system for coordinating the operation of said valvesb to obtain a cycle of operation of the broaching machine in which the carrier moves both with and relative to said ram.

10. An internal broaching machine having, in

ing a first manually actuable device for initiating combination, an upstanding frame, a work supporting ilxture mounted on said frame, a ram for actuating a broach through a pull breaching and a return stroke slidably mounted on said frame for reciprocation relative to said fixture, means carried by the lower end of said ram for chucking one end of the broach, an hydraulic motor for reciprocating said ram, .automatic broach handling mechanism for the other end of the broach including an elevator slidably mounted on the upper end of said ram for movement both with and relative thereto, means on said elevator for releasably chucking said other end of the broach and an hydraulic motor for reciprocating said elevator, an hydraulic system including` a source of fluid under pressure and a plurality of control valves for supplying operating fluidV to said hydraulic motors, certain of-fsaid valves being electrically actuable, and an electrical control system for governing said electrically actuated valves to obtain the desired cycleof operation oi the machine including a manually actuable switch device for initiating downward movement of said elevator relative to said ram, the switch device actuated by said elevator to initiate a broaching stroke of the ram wherebythe ram and elevator vmove jointly, means positively arresting said elevator at the .end of its stroke while the ram continues on its broaching stroke, and 'a switch actuated by said ram for arresting breaching' movement of the ram.

11. In an internalpull breaching machine, a

frame having parallel guideways, a work sup-4 porting fixture mounted on said frame, a main elongated power driven slide mounted in the guideways on said frame-*for reciprocation rela- Vtive to said work supporting fixture, said slide having broach engaging means near one end for one end of a broach and n ar the other end having longitudinally extend' g ways formed therein, and mechanism for handling and'guiding the broach by its other end including an auxiliary carrier slidably mounted in the ways on said main slide and guided throughout its length and throughout its movement by the ways.

, 12. In an internal pull broaching machine, a frame having parallel guideways, a work supporting fixture mounted on said frame, an elongated power driven slide mounted in the guide-v ways on said frame for reciprocation relative to -said work supporting fixture, said slidehaving a main portion with a cylinder formed integrally therewith and an integral extension at one' end having longitudinally extending ways formed therein. broach engaging means on said slide near the end opposite said extension for engaging one end of a broach, and mechanism for'handling and guiding the broach by itsr other end including an auxiliary slide mounted for reciprocation in the ways on said main slide and guided throughout its length and throughout its movement by the ways.

1'3.'An internal pull broaching machine hav-l. ing, in combination, a work supporting fixture, a

a return stroke or said ram while said carrier remains stationary for returning a broach carried by the ram to engagement with chucking means on said carrier, a ram actuatedl control device operable upon actuation to terminate the return stroke of said ram and initiate movement vporting fixture mounted on said frame, a ram for actuating a broach through a pull broaching and a return stroke slidably mounted on said frame for reciprocation relative to said fixture, means carried by the lower endof said ram for chucking one end of the broach, an hydraulic motor for reciprocating said ram, automatic broach handling mechanism for the other end of the broach including an'elevator slidably mounted on the upper end of said ram for movement both with and relative thereto, means on said elevator for releasably chucking said other end of the broach and an hydraulic motor for reciprocating said elevator, an hydraulic system including a source or fluid under pressure and a plurality of control valves for supplying operating fluid to said hydraulic motors, certainA of said valves being electrically actuable, and an electrical control system for governing said electrically actuated valves to obtain the desired cycle of operation of the machine including a manually actuable switch means for initiating a return str'bke of said ram, switch means actuated as an incident to return of said ram toY normal position to arrest return movement thereof and initiate upward movement of said elevator relative to said ram, and switch means actuated by said elevator for arresting the upward movement thereof.

15. An internal broaching machine having, in combination, an upstanding frame, a work supporting fixture mounted on said frame, a ram for upper end of said ram for movement both with and relative thereto, means' on said elevator for releasably chucking the other end of the broach and an hydraulic motor for yreciprocating said elevator, an hydraulic system including a source of fluid under pressure and a plurality of control valves for supplying operating fluid to said hydraulic motors, certain of said-valves being electrically actuable, and an electrical control system for governing said electrically actuated Valves including manually actuable means for initiating a half cycle of operation of the breaching machine and automaticallyV actuated means for coordinating the movements of the main slide and the elevator and for bringing the same to rest at the end of the half cycle of operation of the machine.

16. Aninternal pull broaching machine having,

in combination, a work supporting iixture, a

main slide for actuating the broach mounted for reciprocation relative to said 'work supporting iixture, means mounted on said slide near one end thereof for chucking one end of a broach,

power means i'or reciprocating said main slide, automatic broach handling mechanism for the other end of the broach including. a carrier mounted directly on said slide for movement both relatively to and jointly with said slide and power means for reciprocating said carrier on said slide, and control means for said power means including a carrier actuated control device operable upon actuation to initiate a broaching stroke of said main slide, and a manually actuated control device operable upon actuation to initiate the return stroke of said main slide.

17. An internal pull breaching machine hav-4 ing, in combination, a work supporting iixture, a main slide for actuating the broach mounted for reciprocation relative to said work supporting ilxture, means mounted on said slide near one end thereof for chucking .one end of a broach,

the broach chucking means on the main slide,

a carrier actuated control device operable upon actuation to initiate a broaching stroke ofl said main slide, and a second manually actuated control device operable upon actuation to initiate the' return stroke of said main slide.

FRANCIS J. LAPOINI'E. 

